A US Congress candidate has pepper sprayed himself to demonstrate how teachers could protect against school shootings if they had "non-lethal defence tools in every classroom".

Levi Tillemann, a Democrat candidate in Colorado, says there needs to be legislation to protect children in schools.

"I am calling on congress to pass legislation to place secure a can of high-power pepper spray inside a 'break glass in case of emergency' box in every classroom in the country and train teachers how to use this powerful self-defence tool," he said.

"These boxes should be wired into the school's fire alarms, to help ensure that they are only used in true emergencies."

In a video posted on his YouTube channel, Mr Tillemann voluntarily sprayed himself in the eye with pepper spray.